The present invention relates to devices and methods for treating sleep disordered breathing and, more particularly, to devices which are designed for preventing collapse of airway tissue.
Snoring, excessive daytime somnolence, restless sleep, and obstructive sleep apnea (OSA) are manifestations of sleep-disordered breathing (SDB) which is characterized by abnormalities in respiratory patterns or the quantity of ventilation during sleep.
Obstructive sleep apnea, which is the most common SDB is caused by sleep time collapse of airway tissue forming the pharyngeal wall, soft palate, epiglottis, and/or tongue.
Postural muscle tone is highest in wakefulness, decreased in non-REM sleep, and minimal or absent in REM sleep. Collapse of tissues experienced during REM sleep, leads to a cycle of air flow obstruction, disruption of sleep and arousal.
The recurrent sleep arousal and associated intermittent hypoxia and hypercapnia have been implicated in the occurrence of adverse cardiovascular outcomes. In addition, there is evolving evidence that SDB may contribute to insulin resistance and other components of the metabolic syndrome.
Numerous efforts have been made to treat sleep disordered breathing. These include uvulectomy, nasal reconstruction, adenotonsillectomy, uvulopalatopharyngoplasty (UPPP), genioglossal advancement as well as more complex surgical approaches such as maxillary-mandibular advancement, bimaxillary advancement, and tongue-base surgery.
The type of intervention selected for treatment is based largely on patient physiology and anatomy. A patient with a large uvula who snores and has few or no symptoms of apnea may benefit from uvulectomy or from the Pillar™ implant which is used to stiffen the soft palate.
Relief of nasal obstruction alone rarely cures OSA, however, patient tolerance and response to nasal CPAP are often improved, thus septoplasty, septorhinoplasty, and turbinate reduction may be indicated in patients who have predisposing anatomy.
Adenotonsillectomy is often performed in the pediatric population to correct loud snoring and restless sleep.
Uvulopalatopharyngoplasty (UPPP) is a procedure which is performed most often for treatment of OSA. This procedure includes of tonsillectomy, reorientation of the anterior and posterior tonsillar pillars, and excision of the uvula and posterior rim of the soft palate.
Genioglossal advancement involves performing a mandibular osteotomy with anterior repositioning of the genioglossus-attached segment of the mandible. This procedure results in anterior displacement of the tongue.
Lingual tonsillectomy, lingualplasty, and laser midline glossectomy are procedures designed to reduce the mass of the tongue base. Temperature-controlled radiofrequency tissue ablation (TCRFTA) is used to reduce tissue mass of the tongue base and in the soft palate.
Despite considerable progress in our understanding of these disorders and the development of numerous treatment options, the principal therapeutic approach, continuous positive airway pressure (CPAP) which has been readily available since 1981 and exhibits poor patient tolerability and compliance remains the mainstay SDB treatment to this day.
There is thus a widely recognized need for, and it would be highly advantageous to have, an approach which is effective in treating sleep disordered breathing and yet is safe, minimally or non-invasive, reversible, and tolerable by patients.